Indian flying fox

The Indian flying fox (Pteropus medius), also known as the greater Indian fruit bat, is a species of flying fox native to the Indian subcontinent. It is one of the largest bats in the world. It is of interest as a disease vector, as it is capable of transmitting several viruses to humans. It is nocturnal and feeds mainly on ripe fruits, such as mangoes and bananas, and nectar. This species is often regarded as vermin due to its destructive tendencies towards fruit farms, but the benefits of its pollination and seed propagation often outweigh the impacts of its fruit consumption.

The Indian flying fox was described as a new species by Dutch zoologist and museum curator Coenraad Jacob Temminck in 1825 who gave it the scientific name Pteropus medius. Confusion over the name has prevailed in the literature as in 1782 Danish zoologist Morten Thrane Brünnich, gave the scientific name Vespertilio gigantea as a replacement for Vespertilio vampyrus Linnaeus (1758: 31). He was specifically referring to Linnaeus's use of Vespertillo vampyrus. Carl Linnaeus had previously classified the species as Pteropus vampyrus and as such gigantea could not be used for a species that was already named. In 1992 Corbett and Hill suggested giganteus was a sub-species of vampyrus.

In 2012, Mlíkovský argued that the correct scientific name of the Indian flying fox should be Pteropus medius rather than P. giganteus. He asserted that Brünnich coined a new name for a species that had already been described—Vespertilio vampyrus which is now Pteropus vampyrus (the large flying fox). Mlíkovský made several points in his argument, all with a foundation in the nomenclature rule known as Principle of Priority. The Principle of Priority posits that the first formal, published scientific name given to a species shall be the name that is used. Because Brünnich was attempting to rename the large flying fox in his 1782 publication, his name should not apply to either the large or the Indian flying fox—an older name was in existence, and therefore the large flying fox is P. vampyrus, not P. giganteus; In negating Brünnich's name, Mlíkovský states that the oldest applicable name used to describe the Indian flying fox comes from Coenraad Jacob Temminck's publication in 1825. Mlíkovský's recommendation has been met with varying degrees of acceptance. Some authors who have published on the Indian flying fox since 2012 have accepted this taxonomic revision, using the name Pteropus medius. Other taxonomic authorities, however, such as the Integrated Taxonomic Information System, still recognize Pteropus giganteus as the valid name of the Indian flying fox.

It is most closely related to the grey-headed flying fox, P. poliocephalus. As the genus Pteropus is divided into closely related species groups, the Indian flying fox is placed in the vampyrus species group, which also includes the Bonin, Ryukyu, little golden-mantled, Rodrigues, large, Lyle's, Aldabra, Madagascan, Seychelles, and Mauritian flying foxes.

There are currently three recognized subspecies of the Indian flying fox: P. m. ariel G. M. Allen, 1908, P. m. medius Temminck, 1825, and P. m. leucocephalus Hodgson, 1835.

The Indian flying fox is India's largest bat, and one of the largest bats in the world, weighing up to 1.6 kg (3.5 lb). Its body mass ranges from 0.6–1.6 kg (1.3–3.5 lb), and males are generally larger than females. The wingspan ranges from 1.2–1.5 m (3 ft 11 in – 4 ft 11 in) and body length averages 15.5–22.0 cm (6.1–8.7 in). The wings rise from the side of the dorsum and from the back of the second toe, and its thumb has a powerful claw. It has claws on only its first two digits of its wings, with the thumb possessing the more powerful claw, and all five digits of its leg. It lacks a tail.

The Indian flying fox ranges in color, with a black back that is lightly streaked with grey, a pale, yellow-brown mantle, a brown head, and dark, brownish underparts. It has large eyes, simple ears, and no facial ornamentation—a typical appearance for a species of the genus Pteropus. The skull is oval-shaped and the greatest length of the skull is 71–75.6 mm (2.80–2.98 in). The orbital rim of the skull is incomplete. The ears lack a tragus or antitragus and are ringed, and the ears range in length from 35–40 mm (1.4–1.6 in) in length.

The dental formula is 3.1.4.22.1.4.3. The first upper premolar is absent, the canine is pronounced, and the molars have a longitudinal furrow.